4. Is there a connected nonplanar graph with 7 vertices which is 3- chromatic (it is the minimal number needed for colouring) and has no Euler cycle? Is there such a graph without both an Euler cycle and a Hamiltonian Cycle ? Provide an explanation and drawing with edge interscetions if needed) in both cases if the graph( or graphs) exist 4. Is there a connected nonplanar graph with 7 vertices which is 3- chromatic (it is the minimal number needed for colouring) and has no Euler cycle? Is there such a graph without both an Euler cycle and a Hamiltonian Cycle ? Provide an explanation and drawing with edge interscetions if needed) in both cases if the graph( or graphs) exist